Bright spark

When playing with a piezoelectric spark device taken from a lighter, I created a spark between it and a radiator, and noticed two effects. First, the room lights flickered (the dimmer switch for my lights was partly on, so this may be a factor). Second, when I produced the spark, it caused my computer to declare that the devices plugged into its USB ports had been removed. What caused these effects?

• The lighter is designed to generate sparks only powerful enough for ignition, but the radiator, because it was earthed, drew sparks larger than those intended to jump between the lighter's electrodes. Electrical sparks generate electromagnetic pulses in the form of radio waves and these pulses interfere with all sorts of devices, so manufacturers of various equipment avoid making unnecessarily large sparks.

To appreciate the power of such pulses, remember that for the first several decades of radio technology, ...

To continue reading this article, subscribe to receive access to all of newscientist.com, including 20 years of archive content.

To continue reading this article, log in or subscribe to New Scientist

App + web

Web

Smartphone

Tablet

$25.99 - Save 65%

12 issues for $2.17 per issue

with continuous service

Print + web

Print

Web

$28.99 - Save 61%

12 issues for $2.42 per issue

with continuous service

Print + app + web

Print

Web

Smartphone

Tablet

$39.99 - Save 73%

12 issues for $3.33 per issue

with continuous service

Web

Web only

$49.99

30 day web pass

Prices may vary according to delivery country and associated local taxes.